1. Technical Field
The present invention relates to a light curtain installation method and an interactive display apparatus.
2. Related Art
Recently, an electronic blackboard or an interactive projector, which synthesizes and displays an image based on an image signal input from an external device and an image in which an object such as a character or a picture which corresponds to an operation with respect to an image plane, has been utilized in education and conferences. Such an interactive display apparatus is known, which detects an operation with respect to an image plane using a light curtain. The light curtain radiates light in a plane shape and receives direct or reflective light of the radiated light so as to detect a presence of an object such as a finger. When the light curtain for detecting the operation with respect to the image plane is installed, a position or posture of the light curtain with respect to the image plane needs to be adjusted. For example, a light curtain, which detects an object using reflective light from the object, is adjusted such that only light reflected from the object which is in contact with a certain region of the image plane, of light from the light curtain which travels in parallel with the image plane, is incident to the light curtain.
JP-A-2012-173447 is an example of the related art.
Incidentally, since the light radiated from the light curtain expands in a plane shape, it is not easy to adjust the position or posture of the light curtain with respect to the image plane. For example, the adjustment has to be performed such that the light radiated from the light curtain is in parallel with the image plane when the image plane is viewed from a horizontal direction thereof, and the light radiated from the light curtain is in parallel with the image plane when the image plane is viewed from a vertical direction thereof. In addition, for example, even when the light curtain is installed at a correct position with a correct posture with respect to the image plane, it has to be checked whether light radiated from the light curtain and reflected from the outside of the region of the image plane is detected.